Boehm system clarinet



1939- o. E. CHRHSTENSEN 2,182398 BOEHM SYSTEM CLARINET Filed Feb. 9,1939 Patented Dec. 5, 1939 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates t0 improvemencs in clarinets and pertainsparticularly to the Boehm system clarinet.

In the present conventional Boehm system 1nodel clarinet, the tones Eh(first 1ine of the stafi) ancl Bb (second space above the stafi) whenplayed or produced by the finger position using only the first finger ofeach band covering its respective tone hole (the thumb hole being;overed for both tones anti for the Bb, the twelfth 01 regiser key beingopenecl) show a decidedly unbalanced quality of intonation.

If the tone Bb (played With the above described fingering) is properlytuned, the tone Eb Ls extremely sharp or high and if the tone Eb isproperly tuned, then the tone Bb is extremely fiat or 10W. 'Ihe samesituation exists between the tones E anal B, c-o a slightly lesserextent, and Ehe tones F anol C are also slightly involved.

The present invention has for its primary 0bject er purpose to provide anovel mechanism whereby there may be obtainecl a balance of theintonation of the tones Eb-E and F and BbB and C on a clarinet of theBoehm type.

Another object of the invention is to provide a mechanism whereby theabove described object may be attained, which is of extremely simpledesign and which is made use of or operated without requiring anyalteration in the regular er established fingering of the instrument.

'Ihe invention Will be best understood from a consideration of thefollowing detailed description taken in conneccion with the accompanyingdrawing forming part of this specification, With the understancling,however, that the invention is not 130 be confined to any strictconformity With the showing of the drawing but may be changed ermodified so 1ong as such changes er modifications mark 110 materialdeparture from the salient features of the invention as expressed in theapp8ndecl claims.

In the drawing:

Fig. 1 represents ehe upper main section of a clarinet showing the keymechanism embodying t-he present invention together with certainadjacent keys in spread out relation whereby the relative positions ofthe parts is more readily Seen.

Fig. 2 is a sectional view on the 1ine 2-2 of Fig. 1.

Fig. 3 1's a sectional view on the line 3-3 of Fig. l.

Fig. 4 is a sectional view on the line 44 of Fig. l.

Referring now more particularly so the drawing, the numeral l generallydesignates the upper main section of a clarine1: of the Boehm type, h-eWall struoture of which has been illustrated as laid out er flattenedfor the purpose of more readily illustrating the relative positions ofthe 5 keys anal tone holes.

The numeral 2 designates the standard register key pad which is actuatedby the key 3 pivoced upon the shaft 4, Adjacent the key 3 is ihe usualthumb hole 5 by which the tones F 10 and C are played.

The numerals B, I anal 8 designate respectively the open tone holes ofthe conventional instrument by Whi0h are played respectively the tonesE-B, DA and CG. The tone holes 6 and I normally have associatecltherewith ehe rings 9 and I0, respectively, and the ririg 9 is supportedfor oscillation upon the shaft H and in the comventional Boehm systeminstrument, the ring is also supported upon the shaft H t0 be oseillatedtherevvith, but in the present improved key arrangement, this ring has aseparate support which Will be hereinafter described. Ad- J'acent thetone hole l, a covered tone hole is locaaed over which lies the pad I2which is also carried upon the shaft H and which is closedsimultaneously with the closing of the tone hole J by the second fingerof the left band.

Paralleling the shaft H is a shaft I3 upon which a1e oscillatablymounted the sleeves I4, E5 and I6. The sleeve I4 carries a pad I7 whichoverlies the EbBb tone hole. Connected with the sieeve H5 is a pad I8which covers a tone hole which is particularly described and claimed inmy copending application, Ser. N0. 223545 filed August 6, 1938, by Whichthe FiiCii tones may be played.

In carrying out the present invention, obere is providerl a shaft I9which is suspended by and passes through the alined posts 29 andparaliels the register key 3, preferably being dispoSed in ehe positionshown, that is, between the register key and the shaft 13. Upon theshaft I9 are mounted for indepenclent or joint oscillation the sleeves2I and 22. The sleeve 2I carries an 45 arm 23 which overlies theregister key 3, as shown, so that when this key is depressed, the s1eeve21 Will be rocked. The extent of rocking rnovement of this sleve iscontrolled by the movement limiting foot 24 which merely serves 50 as asafety device Which prevents the accidental turning or rocking of thesleeve to an extent whieh might damage ehe spring 25 which is secured apost and is connected with the sleeve in the conventional manner tocause the arm 23 55 to constantly bear upon the register key in order tomaintain the pad 2 in olosed position.

The sleeve 22 carries an arm 26 which in turn carries a pad 27 whichnormally closes a tone hole 28. Ab the opposite end of the sleeve 22, afinger 29 is supported by the sleeve which positions beneath a finger 33 upon the adjacent sleeve 2I. Through the medium of these overlappingfingers 29 and 3ll, the spring 25 operates o constantly maintain the pad2'! in closed position. There is, however, assooiated with the sleeve22, a spring 3l which is of lighter tension than the spring 25 analwhich operates to insure the raising of the pad 2l when the register keyis depresseol. When this key is released, the spring 25, naturally,because of its greater strength, overcornes the tension I" spring 3! andforces both sleeves 2E-22 to oscillate in the proper direction to olosethe pacls 2 anal 2l.

As previously stated, the ring i?) 1's ordinarily supported ioroscillation an anal Wibll ehe shait H but in the present improvedoonstruction, this ring is carried on. the shaft 533 by the sleeve l andis coupled Wii;h the normally raised pad E2, so that when Zhe ring i isdepressed, bhe pad 52 will also he depressed to close the underlyingtone hole Whioh is particularly illus raed in. Fig 2. The mechanism bywhioh the ring il and pa.d l2 are joined together for the simultaneousoloslng of the pad With the depression of the ring or the olosing of thetone hole l is particularly illustratecl in Fig. 2 wherein the ped ET:has shown attaohed thereto the laterally extending bracket 32 whiohexends under the eclge o:f the edjacent ring 2md this ring is proviciedwith 8, sec screw 33 by which the proper acljusnnent may be made in theconneotion between the ring ancl pad so that they will oper-a1sesrnoothly and without nolse.

Integral With the sleeve 55 with which the ring Hi is connected is anarm 3 lwhioh extends laterally to a position heneath and is normallyspaoed from the arm Whioh is carried by the sleeve 22. The arm 3%operates to prevent the sleeve 32 oseillating and to prevenl; the pad271 being raisecl when che tone hole l is c7osed anal the register keyis opened. As previously stated, when the register l;ey is openedwithout the tone hole i being closed, or in other words, without thering H3 being depressed, then the pad 2l' Will loe raised.

In the use of the instrument with the present improved meohanisrn, whenthe first o index finger of eaeh band is depresseol or covering its tonehole i'or the piaying Bb (seoond speoe above the steif) the register key8 is dopressed With the result hat Ehe additional tone hole which iscovered oy the pad 27 will be opened er, in other worcls, the paol 2"5Will be raisecl. 'Ihis will permit the passage of an additional amountof air through the tone hole to bring the Bb 50ll up to the properpitoh. This explanation is given or made Wih the undersoancling that thelower notes are first to be properly pitched 01 have been properlypitched the instrument, in which case without the addiizion of the tonehole the playing' of -the Bb sone would be too low. By providlng Eheadditional tone hole 28, his is evercome and Bb tone is brought up tothe proper pitch.

In playing the keys E and B, the key of E would oe played oy elosing thetone hole With the finger of the left hand, while the register l;ey isin closed position. By opening the register key, the tone B Will beobtaineol and in ehe ordinary instrument wiish the E properly tune, theB tone would. be 01T or would be 10W. With the present improved devioe,when the register key is opened, the tone hole 28 is opened and the toneB will be brought up to proper pitoh because of the additional airoutlet provided by opening the hole 25.

In instruments where Ehe F tone is properly tuned, the provision of thea.dclecl tone hole 28 facilitate-s the playing of C alt the proper pitohbecause oi the fach that when the register key is opened for playing thetone C, the added tone opening 28 Will be unoovereol anal this willbring the tone C up to the proper pitch Whioh would be ordinariiy tunedslightly low if the F is tuned correotly.

Frorn the foregoing, it Will be readily apparent that Wi;h the neohanism herein described, the proper pitches rnay oe obtained for thosetones which are ordinarily slightly ofi pitoh in a conventionalinstrument and also that this mechnnis1n the added advantage of enablingthe -usician to ootain these tones et the oorreot pitch Withont mekingany changes in the conventional fingering of the instrument.

What is olaimed is:

l. In a Boehm system clarinet, means for bringing the tones Bb, B and C(above the steif) to true picch when the instrument is properly inne-dto Eb E 2Llld F (first line and First space of staff) Whioh oc-mprisesthe addition of a normally olosed aone hole 130 the instrument, anclmeans for opening seid. tone hole simultaneously with the opening of theregister key only when the Eingering employed for producing the seidtones Bb, B and C, the seid means being used i'0r the tones Eb-Bb whenuslng only Ehe EbBb fingering in Which Ehe first' lnger o1 eaoh handcovers its respeetive tone hole.

2. In a Boehno sys'bern clarinet, n1eans for bringing the ones Bb, B andC (above the stafif) to true pitch when the instrument is properly tunedto Eh, E and F (first line and first space o1 staff), whioh eo1nprisesthe addition of a normaily closecl tone hole to the instrument, meansfor opening seid tone hole simultaneously With Ehe opening of theregister key only when the fingering is employed Tor producing the seidtones Bb B anol C, the seid means being used for the tones Eb-Bb whenusing only the Eh-B!) fingering in which the first flngor of each bandoovers its respective tone hole, and means for prevenhing ehe opening ofthe seid addeci tone hole when the register key is open for producingall tones other tnen those first mentioned.

3. In a Boehm systern clarinet, the mechanism ior producing at "armepiteh Ehe tones Bb, B sind C (above the suafi) when the instrument isproperly -:nnecl to produoe the tones Eb, E and F, which oomprises atwomart shaft in whioh each part is mounted upon the instrument iorindependent oscillation, the instrument having a tone hole added theretoadjacent one of seid shaft parts, a pad for seid added hole earried oythe seid one of bhe shafc parts, an operative coupling between the othershaft part and th-e register key, means whereby the two shaft parts Willbe oscillated together to lift seid pad and open the added tone hole,when the register key in openecl for produoing any one of the firstmentionecl tones, anal seid means being designed to facilitate openingthe register k.ey while holding seid pad egainsi; movement for theproduction of aertain other tones.

4. In a Boehm syste1n clarinet the mechanism for producing at true pitchthe tones Bb, B and C when the instrument is properly tuned 130 producethe tones Eh, E and F, which comprises a two-part shaft mounted adjacentthe instrument register key, coupling means between said register keyand one of the shaft parts by which opening of the register key willeffect oscillation 0f the seid shaft part, resilient means normallyurging oscillatlon of the said one shaft part in a. manner co c1ose theregiste1 key, the instrument having an added tone hole adjacent theother shaft part, s. pad carried by said other part and normally closingsaid hole, resilient means normally urging oscillation of the said otherpart in a direction to remove the pad from the added tone hole,connecting means between the shaft parts which is so constructed and.arranged that oscillation 01 ehe first-mentioned part upon opening ofthe register key Will permit the second-mentioned resilient means toremove the pad from said tone hole, the first resi1ient means being ofgreater strength than the second and acting through seid connectingmeans between the shaft parts to hold the pad seated over the tone holeWhen the register key is closed, anal means for retaining the said padin closed position on the added tone hole while fingering the instrumentin Ehe conventional manner when the register key is open for producingall tones other than those first mentioned.

OSCAR E. CHRISTENSEN.

